Molecular Beam Epitaxy

26Molecular Beam Epitaxy for Oxide Electronics

Abhinav Prakash and Bharat Jalan

Department of Chemical Engineering and Materials Science, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA

26.1 Introduction

Metal oxides are the most abundant of all compounds found on Earth, many of which serve as ores for the extraction of pure elements. Initially thought to be passive, oxides are now ubiquitous, finding applications in numerous hand‐held electronic devices – either in the form of display screens or gate dielectrics in transistors. These oxides can be binary (A_mO_x), ternary (A_mB_nO_x), or quaternary. Some of the commonly used binary oxides include silicon dioxide (SiO₂) in field‐effect devices [1] and indium–tin oxide (ITO) as transparent conductors [2]. Over the years, beta‐gallium oxide (β‐Ga₂O₃) has also become popular, owing to its wide bandgap, high room‐temperature electron mobility, and high breakdown voltage [3,4]. Ternary oxides, on the other hand, like barium titanate or lead–zirconium titanate, find applications in transducers due to their piezoelectric properties [5,6]. Recently, alkaline earth stannates have garnered much interest due to their optical transparency, wide bandgap, and high conductivity at room temperature [7–9].

26.2 Structure–Property Relationship in Perovskite Oxides

Among various oxides, one class of materials that has emerged as being of great importance is perovskite oxides. These compounds have a general chemical formula of ABO₃, where ...